int main(void){
  int a,b,i;
  printf("enter two numbers:");
  scanf("%d %d",&a,&b );
  printf("add:%d\n",add(a,b));
  printf("sub:%d\n",sub(a,b));
  printf("mul:%d\n",mul(a,b));
  printf("div:%d\n",div(a,b));
  for(i=0;i<5231;i++);
  return 0;
}

